1 /* $NetBSD: ns_date.c,v 1.1.1.2 2012/09/09 16:08:03 christos Exp $ */
2
3 /*
4 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (c) 1999 by Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
17 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 #ifndef lint
21 static const char rcsid[] = "Id: ns_date.c,v 1.6 2005/04/27 04:56:39 sra Exp ";
22 #endif
23
24 /* Import. */
25
26 #include "port_before.h"
27
28 #include <arpa/nameser.h>
29
30 #include <ctype.h>
31 #include <errno.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <time.h>
35
36 #include "port_after.h"
37
38 #ifdef SPRINTF_CHAR
39 # define SPRINTF(x) strlen(sprintf/**/x)
40 #else
41 # define SPRINTF(x) ((size_t)sprintf x)
42 #endif
43
44 /* Forward. */
45
46 static int datepart(const char *, int, int, int, int *);
47
48 /* Public. */
49
50 /*%
51 * Convert a date in ASCII into the number of seconds since
52 * 1 January 1970 (GMT assumed). Format is yyyymmddhhmmss, all
53 * digits required, no spaces allowed.
54 */
55
56 u_int32_t
ns_datetosecs(const char * cp,int * errp)57 ns_datetosecs(const char *cp, int *errp) {
58 struct tm time;
59 u_int32_t result;
60 int mdays, i;
61 static const int days_per_month[12] =
62 {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
63
64 if (strlen(cp) != 14U) {
65 *errp = 1;
66 return (0);
67 }
68 *errp = 0;
69
70 memset(&time, 0, sizeof time);
71 time.tm_year = datepart(cp + 0, 4, 1990, 9999, errp) - 1900;
72 time.tm_mon = datepart(cp + 4, 2, 01, 12, errp) - 1;
73 time.tm_mday = datepart(cp + 6, 2, 01, 31, errp);
74 time.tm_hour = datepart(cp + 8, 2, 00, 23, errp);
75 time.tm_min = datepart(cp + 10, 2, 00, 59, errp);
76 time.tm_sec = datepart(cp + 12, 2, 00, 59, errp);
77 if (*errp) /*%< Any parse errors? */
78 return (0);
79
80 /*
81 * OK, now because timegm() is not available in all environments,
82 * we will do it by hand. Roll up sleeves, curse the gods, begin!
83 */
84
85 #define SECS_PER_DAY ((u_int32_t)24*60*60)
86 #define isleap(y) ((((y) % 4) == 0 && ((y) % 100) != 0) || ((y) % 400) == 0)
87
88 result = time.tm_sec; /*%< Seconds */
89 result += time.tm_min * 60; /*%< Minutes */
90 result += time.tm_hour * (60*60); /*%< Hours */
91 result += (time.tm_mday - 1) * SECS_PER_DAY; /*%< Days */
92 /* Months are trickier. Look without leaping, then leap */
93 mdays = 0;
94 for (i = 0; i < time.tm_mon; i++)
95 mdays += days_per_month[i];
96 result += mdays * SECS_PER_DAY; /*%< Months */
97 if (time.tm_mon > 1 && isleap(1900+time.tm_year))
98 result += SECS_PER_DAY; /*%< Add leapday for this year */
99 /* First figure years without leapdays, then add them in. */
100 /* The loop is slow, FIXME, but simple and accurate. */
101 result += (time.tm_year - 70) * (SECS_PER_DAY*365); /*%< Years */
102 for (i = 70; i < time.tm_year; i++)
103 if (isleap(1900+i))
104 result += SECS_PER_DAY; /*%< Add leapday for prev year */
105 return (result);
106 }
107
108 /* Private. */
109
110 /*%
111 * Parse part of a date. Set error flag if any error.
112 * Don't reset the flag if there is no error.
113 */
114 static int
datepart(const char * buf,int size,int min,int max,int * errp)115 datepart(const char *buf, int size, int min, int max, int *errp) {
116 int result = 0;
117 int i;
118
119 for (i = 0; i < size; i++) {
120 if (!isdigit((unsigned char)(buf[i])))
121 *errp = 1;
122 result = (result * 10) + buf[i] - '0';
123 }
124 if (result < min)
125 *errp = 1;
126 if (result > max)
127 *errp = 1;
128 return (result);
129 }
130
131 /*! \file */
132